Yea that's how it's supposed to work. Like you can call Chun's leg assist in the middle of a combo to lengthen it, or call her to stuff an opponent in the corner etc. Usually almost any 3 characters work, you just have to figure out which assist you want.
Point char = a character like Wesker that doesn't need meter to deal ridiculous damage
Assist = would be something that should help you create openings/cover you/continue combos
Anchor = would be someone that can use meter and X factor effectively
If you practice simple combos in training mode you will easily beat people online! It's as easy as 1 2 3 4 on the pad then call an assist or super and a character would be half dead.
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